Let $P$ be a point on an elliptic curve $E$.
I know the rule of doubling points - i.e $2P$, $3P$ and so on and I was wondering if there exists, what would be the meaning for $\frac{1}{2}P$, or $\frac{2}{3}P$ or in general $\frac{a}{b}P$ ?
I want to say that I am relatively new in the field of elliptic curves, so I hope this is not a very dumb question.